Improvement in burglar-alarms



W. H. KNOWLES, J1. Burglar-Alarms.

No. 196,023. Patented Oct. 9,1877.

WITNESSES: 1N VENTO/i X A ITO/{N15 VS.

UNITED STATES Pnrrn DFFIoE.

WILLIAM H. KNOWLES, JR., OF CAMDEN, NEW JERSEY.

IMPROVEMENT IN BURGLAR-ALARMS.

Specification forming part of Letters Patent No. 196,023, dated October9, 1877; application filed September 8, 1877.

To all whom it may concern Be it known that I, WILLIAM H. KNowLns, Jr.,of Camden, in the county of Camden and State of New Jersey, haveinvented a certain new and useful Bolt Burglar-Alarm; and I do herebydeclare the following to be afull, clear, and exact description of theinvention, such as will enable others skilled in the art to which itpertains to make and use it, reference being had to the accompanyingdrawings, which form part of this specification, in Which Figure l is aperspective of the alarm. Figs. 2 and 3 are vertical transverse sectionsof a part of the alarm, showing the position of mechanism locking andimlocking the train of gear attached to the alarm. Fig. 4 is a frontelevation, partly in section.

My invention has for its object to provide a burglar-alarm attachmentfor doors, which will be actuated by a very slight movement,insutficient to open the door to which said device is applied.

My invention consists in the combination, with a bolt, of a train ofgearing, a bell or gong, striker, and stop-motion, constructed andarranged, as hereinafter described, so that if the door be moved veryslightly, and not even sufficiently to open the same, the stop-motionwill be released, causing the gearing to be actuated and an alarmsounded.

Referring to the accompanying drawing, A designates a common slidingbolt, having a finger-piece, a. B B B are standards or projections froma plate, C, in which the bolt A is fitted and moved. The centralstandard, B, has a circular opening, I), for the passage of the bolt,while the standards B and B have slotted openings b 0 or elongatedpassages, for the same purpose, these allowing lateral play to said boltat either end. Dis a curved lever, pivoted at d to the standard B havingat its opposite extremity a pin or stud, d,which passes through a slot,0, in a dog, E, pivoted at c to said standard. F is a spring, fastenedat f to the plate 0 and to the stud (1 the office of said spring beingto keep the inner edge d of the lever D in contact with the bolt A. G isa four-armed lever, pivoted at g to the plate C, having also a slot, g,through which passes the shank of a screw or rivet, 9 into said plate C.The arm 9 is beveled, as

shown at g, the arm has a flange or bead, g and the arm is turned up atits end, to form a finger-piece, g. H is a spring, fastened to the plateC at h, and impingingagainst a lug, 9 on the lever G. I is a plate,sustained on posts ii. K is a train of gearing, actuated by a spring, k,and L is a bell or gong, having a striker, l, fastened on a rod, 1,proceeding from the escapement M. N is the main shaft of the gearing, bymeans of which and a key or nut, Q, the latter is wound up. 0 is aratchet-wheel, with which the eseapement M engages, said wheel beingprovided with a stud or pin, 0. P is a shield, secured between thestandards B B to the plate C, slots 1) p at either end preventing thelongitudinal sliding of the bolt, said bolt being rotated in the usualmanner to cause its fingerpiece to enter one of said slots after thebolt has been shot into its keeper.

The object of the two slots 1) p, and the longitudinal movement of thebolt with reference to both, is to permit the device to be applied toleft as well as to right hand doors, it operating equally in eithercase.

The operation is substantially as follows: The plate C is screwed to thedoor, so that the bolt A will occupy the ordinary position of aboltviz., where it can be shot into a keeper, R, secured to thedoor-frame. The spring it having been wound up by means of a nut or key,Q, the lever G is swung on its pivot by taking hold of and pushing upthe finger-piece 9 until the beveled end g of the arm g meets the pin 0on the ratchetwvheel 0, thus preventing the running down of the gearingand the movement of the hammer l. The foot 0 of the dog E, under theinfluence of the spring F, now engages with the flange g of the arm 1operating as a stop, and holding the lever G in the position to which ithas been pushed. The belt A is now (or it may previously have been)slided forward into the keeper R. Now, if the door be moved ever soslightly on its hingesa quarter of an inch will sufiice--it will producea lateral movement of the boltA against the lever l), which, in turning,acting on the dog E, will raise its foot 0 out of engagement with theflange g permitting the lever G to be swung on its pivot under theinfluence of the spring H, moving the end of the arm g away from thestud o, permitting the train of gearing to move, and causing an alarm tobe sounded, and continued until the spring k is fully unwound.

The operation will be substantially the same Where the device is appliedto a letthand door,

only that in such case the lateral movement of the bolt A will cause itto act directly upon the dog E through the tail-piece 6 instead ofintermediately through the lever D, as when on a right-hand door, asabove described.

The bolt A may be moved longitudinally without afi'eeting the alarm,thus permitting the door to be bolted and unbolted ad libz'tum withoutnecessitating unnecessary noise or requiring the frequent winding of thespring.

The bolt subserves all the piu'poses of an ordinary bolt, and may beused as such, and the alarm only comes into play when it is attempted toopen the bolted door without sliding back the bolt.

What I claim as my invention is- 1. The sliding bolt A, sustained instandards or projections B B 13*, the central standard, B,

having a circular opening, b, and the end standards having elongatedslots for the passage of the bolt and the permission of a lateralmovement in the latter, substantially as shown and described.

2. The four-armed lever G, pivoted on the plate C, in combination withthe dog 1*] and stop 0 substantially as shown and described.

3. The combination of lever D, dog E, and spring F with the bolt A andlever G, substantially as shown and described.

4. The combination of sliding bolt A, sustained in standards B B Blevers I) and G, springs F H, gearing K,gong L, and striker I, theseveral parts being secured to acommon base or plate, (3, and arrangedfor operation substantially as shown and described.

In testimony that I claim the foregoing I have hereunto set my hand this28th day of August 1877.

WILLIAM HENRY KNOWLES, JR.

Vt'itnesses:

M. DANL. (JoNNoLLY, CHAS. F. VAN HORN.

